1. See #2
2. CMOS is correct, sometimes these are removable chips.
3. Yes, many motherboards have a jumper to reset to defaults, this is pretty important for overclockers, because you can set the BIOS to settings that are so unstable the computer can't get to the BIOS.

4. Your definition of recent/new is not in alignment with what most people would say is new. Motherboards for a few years now have been shipping with UEFI rather than a traditional BIOS.